I stayed one night in the hotel, for the gamescom.
There is a subway station (U)close by which is handy if you want to go to the centre, as the walk to the Dom is quite long.
The rooms are very tidy and quite big and have a nice clean bathroom.
The elevator is really small though. Not handy with a lot of luggage.
Around the hotel there is not much to do, but they have free maps at the front desk.